chlorcyclizine/pseudoephedrine

Action and Spectrum

Actions and Spectrum: 

chlorcyclizine and pseudoephedrine are active ingredients often found in combination medications for treating various symptoms. 

• chlorcyclizine: This is an antihistamine commonly used to relieve allergy symptoms like runny nose, sneezing, itching of the throat or nose. It works by blocking the effects of histamine, a chemical released during allergic reactions. chlorcyclizine can also have mild sedative effects, which is why it is sometimes included in cough and cold relief medications. 
• pseudoephedrine: pseudoephedrine is a decongestant that narrows the blood vessels in the nasal passages. This helps reduce congestion and swelling, making it easier to breathe. It is often used with other medications to relieve nasal congestion which is caused by colds, allergies, or sinusitis. 

When these two ingredients are combined in a medication, they can relieve multiple symptoms associated with allergies and upper respiratory infections. chlorcyclizine addresses the allergic response, while pseudoephedrine addresses congestion. 

Drug Interaction

Adverse Reaction

Frequency not defined 

Dizziness 

Constipation 

Drowsiness 

Blurred vision 

Restless 

Feeling nervous 

Black Box Warning

Black Box Warning: 

None 

Contraindication / Caution

Contraindication/Caution: 

Contraindication 

• Hypersensitivity: Individuals who have a known hypersensitivity or allergy to chlorcyclizine, pseudoephedrine, or any other ingredients in the medication should not use products containing these ingredients. 
• Severe Hypertension: pseudoephedrine is a decongestant that can increase blood pressure. Individuals with severe or uncontrolled hypertension (high blood pressure) should avoid pseudoephedrine medications. 
• Cardiovascular Disease: pseudoephedrine can have stimulant effects on the cardiovascular system. Individuals with a history of heart disease, arrhythmias, angina, or other cardiovascular conditions should use products containing pseudoephedrine with caution and under the guidance of a healthcare provider. 
• Certain Medical Conditions: chlorcyclizine and pseudoephedrine may be contraindicated in individuals with certain medical conditions, such as glaucoma, hyperthyroidism, diabetes, prostate enlargement (in males), and urinary retention. 
• Monoamine Oxidase Inhibitors (MAOIs): Products containing pseudoephedrine are generally contraindicated in individuals who are taking or have recently taken MAOIs or within two weeks of discontinuing MAOI therapy. Combining these medications can lead to a potentially dangerous increase in blood pressure. 
• Pregnancy and Breastfeeding: The safety of chlorcyclizine and pseudoephedrine during pregnancy and breastfeeding is not well established. It’s recommended to consult the healthcare provider before using medications containing these ingredients if you are pregnant or breastfeeding. 
• Children: Some medications containing these ingredients may not be suitable for children under a certain age. Always follow the age-specific dosing instructions on the medication packaging or a healthcare professional’s advice. 
• Prohibited in Certain Sports: pseudoephedrine is listed as a prohibited substance by some sports organizations due to its potential stimulant effects. Athletes should be cautious and aware of the regulations of their respective sports. 

Caution 

• Central Nervous System Effects: chlorcyclizine and pseudoephedrine can cause central nervous system (CNS) side effects, including dizziness, drowsiness, and impaired coordination. These effects may be more pronounced when taking higher doses/in combination with alcohol or other medications that have CNS depressant effects.  
• Combination Products: chlorcyclizine and pseudoephedrine are often found in combination with other active ingredients in multi-symptom cold and allergy medications. Be aware of the total content of active ingredients in the medication to avoid accidental overdose or duplication with other products. 
• Cardiovascular Effects: pseudoephedrine can stimulate the cardiovascular system and raise blood pressure. Individuals with a history of heart conditions, high blood pressure, arrhythmias, or other cardiovascular issues should use products containing pseudoephedrine with caution and under the guidance of a healthcare provider. 
• Thyroid Disorders: pseudoephedrine can affect thyroid function and should be used cautiously by individuals with hyperthyroidism (overactive thyroid). 
• Prostate Enlargement: pseudoephedrine may exacerbate symptoms of prostate enlargement (benign prostatic hyperplasia) in males. Consult a healthcare provider before using pseudoephedrine products if you have this condition. 
• Diabetes: pseudoephedrine can affect blood sugar levels and should be used cautiously by individuals with diabetes.  
• Glaucoma: chlorcyclizine and pseudoephedrine may increase intraocular pressure and worsen the symptoms of glaucoma. Individuals with glaucoma should consult a healthcare provider before using products containing these ingredients. 
• Interaction with Other Medications: chlorcyclizine and pseudoephedrine may interact with other drugs, including prescription, over-the-counter, and herbal supplements. Consult a healthcare provider or pharmacist before using these medications alongside others. 
• Pregnancy and Breastfeeding: The use of medications containing chlorcyclizine and pseudoephedrine during pregnancy and breastfeeding should be discussed with a healthcare provider. The safety of these medications in these situations is not well established. 
• Age Considerations: Some medications containing these ingredients may not be suitable for young children. Always follow age-specific dosing instructions and consult a healthcare provider for guidance. 
• Allergic Reactions: If you experience any signs of the allergic reaction, like rash, itching, swelling, severe dizziness, or difficulty breathing, discontinue use and seek medical attention. 

Pregnancy / Lactation

Pregnancy consideration:  

US FDA pregnancy category: Not assigned 

Lactation:   

Excreted into human milk: Yes. 

Pregnancy category: 

• Category A: well-controlled and Satisfactory studies show no risk to the fetus in the first or later trimester. 
• Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women. 
• Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.    
• Category D: adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.    
• Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women.    
• Category N: There is no data available for the drug under this category. 

Pharmacology

Pharmacology: 

chlorcyclizine is an antihistamine that competes with histamine for H1 receptor sites, thereby reducing the symptoms of allergic reactions, like itching, sneezing, and runny nose. pseudoephedrine is a sympathomimetic decongestant that stimulates alpha-adrenergic receptors in the nasal mucosa, leading to vasoconstriction and reduced swelling of nasal passages, effectively relieving nasal congestion associated with allergies and colds.

It also stimulates beta-adrenergic receptors, leading to bronchial relaxation and mild stimulant effects, while its potential to increase blood pressure warrants caution in individuals with cardiovascular conditions. The combination of chlorcyclizine and pseudoephedrine in certain medications aims to relieve various allergy and cold symptoms by targeting histamine-mediated responses and nasal congestion through complementary mechanisms. 

Pharmacodynamics: 

Mechanism of action: chlorcyclizine is an antihistamine that primarily acts by competitively blocking the effects of histamine at H1 receptors. Histamine is a chemical released by cells during allergic reactions, leading to itching, sneezing, runny nose, and watery eyes. By binding to and blocking H1 receptors, chlorcyclizine reduces the effects of histamine, thereby alleviating these allergic response symptoms. Additionally, chlorcyclizine can have mild sedative effects because of its ability to cross the BBB (blood-brain barrier) and affect central nervous system activity. 

pseudoephedrine is a sympathomimetic decongestant that stimulates alpha-adrenergic receptors in the nasal mucosa and other blood vessels. This stimulation leads to vasoconstriction, or narrowing of blood vessels, which diminishes blood flow and swelling in the nasal passages. As a result, nasal congestion is relieved, making it easier to breathe. pseudoephedrine also has some beta-adrenergic receptor activity, leading to bronchial relaxation and mild stimulant effects. Due to its vasoconstrictive properties, pseudoephedrine can raise blood pressure, and caution is advised in individuals with cardiovascular conditions. 

When chlorcyclizine and pseudoephedrine are combined in certain medications, they provide a synergistic approach to managing symptoms associated with allergies, colds, and nasal congestion. 

Pharmacokinetics: 

Absorption 

chlorcyclizine is rapidly and well absorbed from the gastrointestinal tract after oral administration. 

pseudoephedrine is also well absorbed after oral administration, with peak plasma concentrations typically achieved within a few hours. 

Distribution 

It has a high distribution volume and can cross the blood-brain barrier, contributing to its potential for central nervous system effects. It is also bound to plasma proteins. 

It has a moderate distribution volume and can cross the blood-brain barrier, leading to potential central nervous system effects. It is also bound to plasma proteins. 

Metabolism 

chlorcyclizine undergoes hepatic metabolism primarily through oxidation and conjugation pathways. 

pseudoephedrine undergoes hepatic metabolism through processes like N-demethylation and oxidation. 

Elimination and Excretion 

The metabolites are generally excreted in the urine, with a short elimination half-life. 

The metabolites are generally excreted in the urine, with an elimination half-life that can vary between individuals. 

Adminstartion

Administration: 

chlorcyclizine and pseudoephedrine are commonly found in combination medications that relieve symptoms such as allergies, colds, and nasal congestion. These medications typically come in various forms, including tablets, capsules, liquids, and extended-release formulations.  

Dosage and Frequency: Follow the medication packaging’s recommended dosage and frequency instructions. Dosage might vary based on the specific product and the individual’s age.  

Oral Administration: Most products containing chlorcyclizine and pseudoephedrine are taken orally. This typically involves swallowing tablets or capsules with water. Some products may be taken with or without food, but following the instructions is essential. 

Extended-Release Formulations: If using an extended-release formulation, such as a long-acting tablet, it’s important to swallow the tablet whole and not crush, chew, or break it. Extended-release formulations are designed to release the medication slowly over time. 

Liquid Formulations: If using a liquid formulation, carefully measure the prescribed dose using a calibrated measuring device, such as a dosing cup or syringe, to ensure accurate dosing. 

Age and Weight Considerations: Consider age-specific dosing recommendations, especially for pediatric use. Some products may have age and weight restrictions, so follow the instructions for the specific age group. 

Time of Administration: Follow the recommended dosing schedule. Some medications must be taken multiple times daily, while others may have a once-daily dosing regimen. Be consistent with the timing of doses to maintain a steady level of medication in your system. 

Avoid Alcohol and CNS Depressants: As chlorcyclizine and pseudoephedrine can have central nervous system (CNS) effects, it’s advisable to avoid alcohol and other medications that have CNS depressant effects while using these medications. 

Duration of Use: Use the medication for the duration specified on the packaging/as directed by a healthcare provider.  

Interactions with Other Medications: Be aware of potential interactions with medications you may be taking. Consult a healthcare provider or pharmacist if you are unsure about potential interactions. 

Storage: Store the medication according to the instructions on the packaging. Keep it out of reach of children and away from moisture and direct sunlight. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: chlorcyclizine/pseudoephedrine 

Pronounced: [ klor-SIK-li-zeen-and-SOO-doe-ee-FED-rin ] 

Why do we use chlorcyclizine/pseudoephedrine? 

chlorcyclizine and pseudoephedrine are commonly used active ingredients in combination medications that relieve various symptoms associated with allergies, colds, and respiratory congestion. These ingredients work together to address multiple symptoms simultaneously.  

• Allergy Relief: chlorcyclizine is an antihistamine that helps alleviate symptoms like runny nose, sneezing, itchy or watery eyes, and itching of the throat/nose that are often caused by allergic reactions to substances such as pollen, dust, pet dander, and certain foods. 
• Nasal Congestion: pseudoephedrine is a decongestant that narrows blood vessels in the nasal passages. It helps reduce congestion and swelling, making it easier to breathe.  
• Cough Relief: Some combination medications containing chlorcyclizine and pseudoephedrine may also help alleviate cough symptoms, particularly when the cough is associated with congestion or postnasal drip. 
• Cold and Flu Symptoms: These ingredients can be found in multi-symptom cold and flu medications to address a combination of symptoms, such as runny nose, sneezing, congestion, and mild coughing. 
• Upper Respiratory Infections: chlorcyclizine and pseudoephedrine may be used to manage symptoms of upper respiratory infections, such as the common cold. 
• Sinusitis: The decongestant properties of pseudoephedrine can help manage sinus congestion and discomfort associated with sinusitis. 
• Hay Fever: chlorcyclizine and pseudoephedrine may relieve hay fever symptoms, which is an allergic reaction to pollen or other airborne allergens. 
• Seasonal Allergies: These ingredients are commonly used during allergy seasons to manage the symptoms of seasonal allergies, such as itching, sneezing, and congestion.